From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2B3CBCA0FF2 for ; Wed, 3 Sep 2025 11:48:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=UpoJObt3fXHmnCgApXAd+PJkE0iJXu1bG38S0G7zckA=; b=ThZ5kF50UKv2q/1hrMRdFlODCQ /7ESYAEUGspYAHBKqQ81FHSZiFgag8yGaDJm2gjEcxdzk7pn604ScdU3kUcMZCVlmsmZEmJiTEygL mQq4UDHFi5E/vlkJuAOuYaST8Wer40yBbXHc/EJHX8UlZMepsnBfsj4jbxql1MK4RwxpBF4i1OgXv Hy/Zg0Z2QKIenAeqGr4J4ndzXZZ5/MKuJNsjyIUQ3gOnUh0erAz0bGjfw2Dcdl3Avht2BCyNGsTzQ NQ+Y7o3nh4JCENKgvlhMZMj+1C6j6XyzgnlqnwBH4v8zXwzM4vzuH9/rPBxNLMKtd/BI/FnZ+98kf 9hzOEefg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1utlyQ-00000006GeY-1Vku; Wed, 03 Sep 2025 11:48:22 +0000 Received: from mgamail.intel.com ([198.175.65.12]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1utkt2-000000067Rs-2VnO; Wed, 03 Sep 2025 10:38:45 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1756895924; x=1788431924; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=GCTF1UYtOSCeRAlhubdQAJ7qhlBqyZpfpnhA1MMIZJE=; b=aoIeSVfgjxBHaBK/rH7eeDtjQn6Q93RiB9ABmLVlCPmjCKXUIIPqN/nV KM0cssTP95HMkBWKzLY0/l3d8NRTnpcK4PWYron/+JrhboKVkBl4U3S13 Bh5pybcx0vaY35wVOE8ZSR9zcTmuu0lWla6FXzgj2yW3A871RzNYklG+s H6Wx/gRMJ2u06zDiAGYIDycA0GJ4+I49tlpOw8m68CWbTRw1S4FJDiAl1 WR4uza9hQ6vvJnArbqe30TMsnQqJIvR1ViQWKsDWHtb2oW+AsD9Qwz3C+ F8G8jGU51Sa5bgwGByzQnnOOdHZt4KSMXnrBor9D/06I8fGrJSaACIqMA w==; X-CSE-ConnectionGUID: Ors3eccARVC0EZZbjhmDMQ== X-CSE-MsgGUID: vHbF1tytT8KLR/1r665UIA== X-IronPort-AV: E=McAfee;i="6800,10657,11541"; a="70632578" X-IronPort-AV: E=Sophos;i="6.18,233,1751266800"; d="scan'208";a="70632578" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Sep 2025 03:38:43 -0700 X-CSE-ConnectionGUID: gcUgIZtvSDO2dFM95UNdfw== X-CSE-MsgGUID: hQkiLlfsRpSs+9G/ykDw9A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,233,1751266800"; d="scan'208";a="202430131" Received: from smile.fi.intel.com ([10.237.72.52]) by orviesa002.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Sep 2025 03:38:33 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.98.2) (envelope-from ) id 1utksl-0000000AxU5-0dpr; Wed, 03 Sep 2025 13:38:27 +0300 Date: Wed, 3 Sep 2025 13:38:26 +0300 From: Andy Shevchenko To: Bartosz Golaszewski Cc: Andy Shevchenko , Linus Walleij , Bjorn Andersson , Konrad Dybcio , Alexey Klimov , Lorenzo Bianconi , Sean Wang , Matthias Brugger , AngeloGioacchino Del Regno , Paul Cercueil , Kees Cook , Andy Shevchenko , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Dong Aisheng , Fabio Estevam , Shawn Guo , Jacky Bai , Pengutronix Kernel Team , NXP S32 Linux Team , Sascha Hauer , Tony Lindgren , Haojian Zhuang , Geert Uytterhoeven , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Neil Armstrong , Mark Brown , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-hardening@vger.kernel.org, linux-mm@kvack.org, imx@lists.linux.dev, linux-omap@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Bartosz Golaszewski , Konrad Dybcio Subject: Re: [PATCH v7 16/16] pinctrl: qcom: make the pinmuxing strict Message-ID: References: <20250902-pinctrl-gpio-pinfuncs-v7-0-bb091daedc52@linaro.org> <20250902-pinctrl-gpio-pinfuncs-v7-16-bb091daedc52@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250903_033844_675944_4CCF3897 X-CRM114-Status: GOOD ( 24.91 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Wed, Sep 03, 2025 at 12:34:00PM +0200, Bartosz Golaszewski wrote: > On Wed, Sep 3, 2025 at 12:22 PM Andy Shevchenko > wrote: > > On Wed, Sep 03, 2025 at 09:33:34AM +0200, Bartosz Golaszewski wrote: > > > On Tue, Sep 2, 2025 at 10:46 PM Andy Shevchenko > > > wrote: > > > > On Tue, Sep 2, 2025 at 8:42 PM Bartosz Golaszewski wrote: > > > > > On Tue, Sep 2, 2025 at 4:38 PM Andy Shevchenko > > > > > wrote: > > > > > > On Tue, Sep 02, 2025 at 01:59:25PM +0200, Bartosz Golaszewski wrote: ... > > > > > > > The strict flag in struct pinmux_ops disallows the usage of the same pin > > > > > > > as a GPIO and for another function. Without it, a rouge user-space > > > > > > > process with enough privileges (or even a buggy driver) can request a > > > > > > > used pin as GPIO and drive it, potentially confusing devices or even > > > > > > > crashing the system. Set it globally for all pinctrl-msm users. > > > > > > > > > > > > How does this keep (or allow) I²C generic recovery mechanism to work? > > > > > > Anyway, what is your point? I don't think it has any impact on this. > > > > If we have a group of pins that are marked as I²C, and we want to use recovery > > via GPIOs, would it be still possible to request as GPIO when controller driver > > is in the strict mode? > > Yes, if you mark that function as a "GPIO" function in the pin > controller driver. How would it prevent from requesting from user space? -- With Best Regards, Andy Shevchenko